Jump Ring Calculator

Calculate jump ring dimensions and aspect ratios from mandrel size and wire gauge. See which chainmaille weaves your rings will work with.

The outer diameter of your mandrel or dowel.

Auto-fills wire diameter below.

Or enter directly to override gauge.

Inner Diameter

4.00mm


Outer Diameter

6.05mm

Aspect Ratio

3.91AR

Rings per Inch of Mandrel

24.8rings/in

Wire per Ring

15.78mm

Aspect Ratio Reference

Highlighted row matches your current AR (3.91).

AR RangeCompatible Weaves
2.5 – 31-in-1 chain
3 – 3.5Byzantine, Box chain
3.5 – 4Full Persian, Jens Pind
4 – 5European 4-in-1, Dragonscale
5+Japanese patterns, Loose weaves

Tips

  • Rings spring back slightly after cutting — actual ID may be 0.1-0.2mm larger than mandrel size.
  • For consistent rings, wind your coil tightly and use a jeweler's saw (not flush cutters) for clean ends.
  • Aspect ratio is the most important number for chainmaille — it determines which weaves will work.